BUFFALO SOCIETY OF NATURAL SCIENCES 179 



20 Diaphorus leucostoma var. infuscatus n. var. 



-Male : Very much like D. leucostoma. Length 3.3 mm. 

 Hind tibiae have their tips blackish, hind tarsi entirely blackish; 

 the third vein is bent backward slightly more than in leucostoma 

 and the second vein extends somewhat further towards the apex 

 of the wing. 



Two males Washington, D. C. and N. J. 



The three species belonging to the leucostoma group, which 

 have the eyes widely separated by the front, the cilia of the 

 tegulae pale, the third joint of the antennae as long as the two 

 basal joints and with a pointed tip are separated as follows ; 

 leucostoma has the face distinctly longer than wide, the hind 

 tibiae yellow, the fore femora with rather short hairs on the 

 lower side, and the thorax green with more or less coppery or 

 golden reflections. The other two have the thorax bluish, the 

 face nearly or quite as wide as long, and the hind tibiae brown- 

 ish or blackish. In quadratits the hind femora have rather long 

 hairs on top and only short hairs below, the face almost square, 

 and the third joint of the antennae with a rather sharp point ; 

 while in occidentalis the face is slightly longer than wide, there 

 are long bristly hairs on the lower outer edge of all femora, and 

 the hairs on the top of the hind femora are no longer than on 

 the sides. 



21 Diaphorus quadratus n. sp. 



Male : Length 3 mm. Face very wide, nearly square, so 

 thickly covered with silvery white pollen as to conceal the ground 

 color, rather -flat with a depressed line in the center, deepest 

 near the antennae and not reaching the oral margin ; palpi small, 

 brownish with pale edges and white pollen ; front as wide as the 

 face with nearly parallel sides, bluish green, with white pollen 

 which is thickest near the antennae ; antennae black, third joint 

 large with a long point (Fig. 10), arista inserted before the tip 

 of this point ; lower and lateral orbital cilia white and rather 

 long. Thorax blue-green, dulled with gray pollen ; pleurae green 

 with blue reflections in front of the middle coxae. Scutellum 

 and abdomen bright green, shining, abdomen depressed, the 

 hairs on the sides and venter yellowish, stiff as are also the black 

 hairs on the dorsum, the bristles on the posterior margins of the 



